package page2;

import java.util.Scanner;

public class Ques1769 {
	
	public void go(){
		Scanner scan = new Scanner(System.in);
		int n;
		int sum;
		while(scan.hasNext()){
			sum = 1;
			n = scan.nextInt();
			
			for(int i = 1; i <= n / 2;i++){
				sum += n / i;
			}
			sum += n/2;
			System.out.println(sum);
		}
	}
	
	public static void main(String[] args) {
		new Ques1769().go();
	}
}
